Is there where your man cave is at? Now I understand how amps with more heat dissipation would rank better. My bad.Maybe you should be in basement-fi rather than summit-fi
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Is there where your man cave is at? Now I understand how amps with more heat dissipation would rank better. My bad.Maybe you should be in basement-fi rather than summit-fi
On the topic, I can finally share some data from testing my Lundahl LL1630 setup and limited testing with all the gear I have available... It's fascinating to see it all plotted out and compare STAX gear to transformer setup. The STAX SRM-1 surprised me with its low end performance but also how quickly it falls off, also interesting was its behaviour changing quite dramatically based on the load used. Even a 2 wire reading from my oscilloscope (1mOhm) would drag down its output significantly...
<< snip snip >>
What was used:
STAX SRM-1 mk2 (Fully restored and calibrated)
STAX SRD-7 modified with 4.7ohm resistors and switching removed (performed the best compared to my other SRDs)
Lundahl LL1630 - Driven by Topping LA90 Monoblocks (Roughly 90Wpc)
Lundahl LL1630 - Driven by Sony TA-N9000ES (Roughly 200Wpc)
Lundahl LL1630 - Driven by Luxman LV103 Tube / MOSFET Hybrid (Roughly 75Wpc)
Lundahl LL1630 - Driven by Encel CSM-40 OT Tube (Roughly 18Wpc)
Not aware of any mods for the SRM-1mk2 only the SRM-T1? The restoration included new trimpots, diodes and all new capacitors except the polystyrenes. Outputs were removed and reseated with new thermal paste.I know less about electronics than fish know about bicycles, but this really shows some very different stuff. INTERESTING!
You said the STAX SRM-1 mk2 is "fully restored and calibrated" ... so no CC mod (?constant current) ?
Same amp I'm using to drive pre-Lxxx lambdas. Mine is probably not well-calibrated. My hearing cuts off at 14.5k so I don't detect much of the high freq dropoff. Guess I know why the Stax almost never sound too bright and edgy to me.
Did I mention Very Interesting? Thanks for sharing.
Whoa whoa whoa, let’s not put down basement man caves. I’ve seen some good ones and I’ll be rocking one eventually. Any dedicated space that can be carved out is a winIs there where your man cave is at? Now I understand how amps with more heat dissipation would rank better. My bad.
it's simply awesome, thank you for sharing such valuable dataOn the topic, I can finally share some data from testing my Lundahl LL1630 setup and limited testing with all the gear I have available... It's fascinating to see it all plotted out and compare STAX gear to transformer setup. The STAX SRM-1 surprised me with its low end performance but also how quickly it falls off, also interesting was its behaviour changing quite dramatically based on the load used. Even a 2 wire reading from my oscilloscope (1mOhm) would drag down its output significantly...
In contrast the Lundahl LL1630 just doesn't give a crap really, it will deliver consistent results regardless of what load I put on it and is basically flawless across the FR (voltage output), its only limitation seems to be its fall off at 20hz and lower (270Vrms limit when the core saturates) it may be possible to work around this with a different winding configuration or possibly series them???
Out of the amplifiers used, the Topping LA90 was the most linear, clean and consistent from what I saw and 2 of them fit nicely on a desk with balanced inputs used. Also threw in some random testing with different amplifiers to see how it impacts the response and also a 1960s Encel tube amplifier for the LOLs of "tube sound"
Tried various loads from 120pF capacitor to 150kOhm resistor with capacitor in series / parallel and ended up settling on the 120pF capacitor alone with a single wire reading off my scope and multimeter (10mOhm) to give the SRM-1 a fair chance. I chose 150Vrms as the reference based on my listening levels.
What was used:
STAX SRM-1 mk2 (Fully restored and calibrated)
STAX SRD-7 modified with 4.7ohm resistors and switching removed (performed the best compared to my other SRDs)
Lundahl LL1630 - Driven by Topping LA90 Monoblocks (Roughly 90Wpc)
Lundahl LL1630 - Driven by Sony TA-N9000ES (Roughly 200Wpc)
Lundahl LL1630 - Driven by Luxman LV103 Tube / MOSFET Hybrid (Roughly 75Wpc)
Lundahl LL1630 - Driven by Encel CSM-40 OT Tube (Roughly 18Wpc)
How about this thing from Topping: https://apos.audio/products/topping-eha5-electrostatic-amplifier?_pos=1&_sid=63876f77b&_ss=rHey all. So I tried some STAX Lambdas 4-5 years ago at a hi-fi shop, I think it was either the L500s and L700s or the L300s and L500s, can't remember which but I and my dad were definitely wow'd and talking about them excitedly the entire drive home. They seemed to knock it out the park with any genre.
Cut to a couple weeks ago when I'd mostly forgotten about electrostats and had an itch to research the Sennheiser HD800S as a potential buy. Then suddenly I realised that a specialised headphone that sounds bad with rock and electronic music is not something I want.
So now I'm thinking that in the end it always comes back to STAX. I want to go for some L700 Mk2s, but the fact remains I still need an energiser. I'm looking at a used D50 right now that could be a purchase. Honestly, I want to avoid tubes but the Woo WA7e might've swung me if it was more easily available in the UK. Another possibilty is an SRM-400S, but my DAC, a Burson Audio Composer 3XP, is currently hooked up to my desktop speakers. I'm guessing I'd have to fiddle with cables every time I want to switch between.
Is it okay to buy used for energisers? Any other possibilities?
Budget is a bit tight because I'm moving and have spent a fair bit on other things recently.
Yes, very interesting data, thank you @aokman !On the topic, I can finally share some data from testing my Lundahl LL1630 setup and limited testing with all the gear I have available... It's fascinating to see it all plotted out and compare STAX gear to transformer setup. The STAX SRM-1 surprised me with its low end performance but also how quickly it falls off, also interesting was its behaviour changing quite dramatically based on the load used. Even a 2 wire reading from my oscilloscope (1mOhm) would drag down its output significantly...
In contrast the Lundahl LL1630 just doesn't give a crap really, it will deliver consistent results regardless of what load I put on it and is basically flawless across the FR (voltage output), its only limitation seems to be its fall off at 20hz and lower (270Vrms limit when the core saturates) it may be possible to work around this with a different winding configuration or possibly series them???
Out of the amplifiers used, the Topping LA90 was the most linear, clean and consistent from what I saw and 2 of them fit nicely on a desk with balanced inputs used. Also threw in some random testing with different amplifiers to see how it impacts the response and also a 1960s Encel tube amplifier for the LOLs of "tube sound"
Tried various loads from 120pF capacitor to 150kOhm resistor with capacitor in series / parallel and ended up settling on the 120pF capacitor alone with a single wire reading off my scope and multimeter (10mOhm) to give the SRM-1 a fair chance. I chose 150Vrms as the reference based on my listening levels.
What was used:
STAX SRM-1 mk2 (Fully restored and calibrated)
STAX SRD-7 modified with 4.7ohm resistors and switching removed (performed the best compared to my other SRDs)
Lundahl LL1630 - Driven by Topping LA90 Monoblocks (Roughly 90Wpc)
Lundahl LL1630 - Driven by Sony TA-N9000ES (Roughly 200Wpc)
Lundahl LL1630 - Driven by Luxman LV103 Tube / MOSFET Hybrid (Roughly 75Wpc)
Lundahl LL1630 - Driven by Encel CSM-40 OT Tube (Roughly 18Wpc)
Yes it seems quite tricky to find an accurate load and need to try and read between the lines by trying different things and seeing how it changes the output. I cannot say I saw any real difference between different capacitor types, adding resistors / capacitors as a load etc. I have that data also if it’s of any use to anyone, I can share also, but only the SRM-1 really changes a lot… I may be missing something in regards to that? Wish I had more direct drive examples to explore. To me so far, the greatest benefit of a good transformer setup seems to be consistent, stable performance, regardless of what estats you throw at them…Yes, very interesting data, thank you @aokman !
Not that I know circuits, but this definitely gels with what the Stax Mafia has discussed before -- with many of the direct drive electrostatic amps, higher output device bias extends the high frequency response (not low frequency). Of course this comes at the expense of great heat dissipation, etc. I remember when KGSShv Carbon was new, many builders purposely backed off the bias from 20mA to say 16 or 17mA, specifically to improve its sonic match to 009.
The transformers struggle on the opposite side of the spectrum, in bass. Not that what you show is of concern -- they seem to acquit themselves very well. But I think its performance might be very dependent on the actual reactive load presented by the headphones?
The SRM-1 is very low powered compared to the "Mafia" amps like KGSShv / etc, and I think that reflects in its poor high frequency performance at higher volume levels. As a loud listener I have heard the Stax amps (727) fall apart as you push volume. They're not stellar at lower volume either but they really struggle as you push it. This is a different world from dynamics headphones & amps -- where you can very easily have such ludicrous amount of headroom that power will never be a concern. I have experienced at least some correlation between the power consumption of direct-drive electrostatic amps and the subjective sound quality, which is why I found Dr. Kevin Gilmore's listing interesting.
You said the STAX SRM-1 mk2 is "fully restored and calibrated" ... so no CC mod (?constant current) ?
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Hi @kevin gilmore , was wondering if you could take a quick look at this and share any thoughts. Not so much concerning audio quality, but safety for the headphones being used. As the product has relation to the iESL, and this was birgirs comments about the iESLalmost all of the stax made solid state amps already have constant current sources in the output stage.
for sure srmxh,srm252,smr313,srm323,srm353,srm717,srm727,srm500s,srm700s,srm-t8000
and probably a few others i forgot.
Mmm, the price is great but I have a Topping PA5 that failed completely in one channel after 6-8 months and had to go back. From a quick ASR survey, something like 30% of buyers experienced the same. I’m a little wary.How about this thing from Topping: https://apos.audio/products/topping-eha5-electrostatic-amplifier?_pos=1&_sid=63876f77b&_ss=r
I hear you - and I'm not advocating it other than it's inexpensive.Mmm, the price is great but I have a Topping PA5 that failed completely in one channel after 6-8 months and had to go back. From a quick ASR survey, something like 30% of buyers experienced the same. I’m a little wary.
right choice, totally agreegoo for one of the Carbons or KGGG or other custom built amps out there